I have read on this forum that an O-ring may be a good solution but I have not tried it myself. If you do end up disassembling the ball, you may want to consider it. Maybe some other bolters could chime in about their experience with the O-ring.

http://www.oreillyauto.com/site/c/detail/NAT0/327.oap?ck=Search_327_-1_-1&keyword=327


Ed